Beer and other beverages are commonly served in restaurants in large pitchers. Although breweries recommend that their product be served at thirty eight degrees Fahrenheit, the product heats up quite rapidly once served. The liquid in the bottom of a large pitcher will warm up to a temperature quite in excess of the ideal serving temperature by the time it is consumed. Thus, the customer's memory of the product is that it was quite tasty at first but somewhat disappointing later.
Several inventors have developed containers for keeping liquids cold, although not all of them have addressed the problem of cooling potables in large containers such as pitchers. For example, U.S. Pat. No. 5,044,173 to Cheng discloses a small cup having a hollow stick that screws into the cup from its bottom. A freezable liquid fills the hollow stick and keeps cold the liquids poured thereabout. The problem with this particular arrangement of parts is that the hollow stick must be kept meticulously clean because the liquid comes into direct contact with it. Thus, if the hollow stick and the liquid contained therein are placed in a freezer, the inside of the freezer must be clean so as to avoid contamination of the hollow stick and consequently of the liquid within which it will be immersed. Even if the inside of the freezer is kept clean, the hands of the individual inserting the hollow stick into the cup may not be.
An approach that avoids use of an insertable hollow stick is shown in U.S. Pat. No. 5,001,907 to LaCroix et. al. A cup is formed to have an annular chamber about the liquid-containing central cavity, and a freezable material is placed in the annular chamber. The problem with this combination of elements is that the entire cup must be placed in the freezer in order to freeze the freezable material. This is an impractical solution to the problem if applied to large pitchers.
All of the known containers for cooling liquids fall into the categories defined by Cheng and LaCroix et. al., i.e., all of the cooling inserts come into direct contact with the liquid being cooled, or the entire container must be frozen or cooled. See U.S. Pat. No. 4,531,383 to Zimmermann, U.S. Pat. No. 2,734,358 to Himmelfarb, U.S. Pat. No. 5,009,083 to Spinos et. al., U.S. Pat. No. 4,981,022 to Snyder, U.S. Pat. No. 3,840,153 to Devlin, and U.S. Pat. No. 5,067,328 to Medina et al.
Clearly, at the time the present invention was made, the prior art, when considered as a whole in accordance with the requirements of law, neither taught nor suggested to those of ordinary skill in the art how a breakthrough in such art could be achieved.